2020-05-27 15:29:27.805 T:2875597680 DEBUG: FindMovie: Searching for 'Die Fosters' using The Movie Database scraper (path: '/storage/.kodi/addons/metadata.tvshows.themoviedb.org', content: 'tvshows', version: '3.5.3')
2020-05-27 15:29:27.825 T:2875597680 DEBUG: scraper: CreateSearchUrl returned <url cache="tmdb-search-Die%20Fosters-de.json">https://api.tmdb.org/3/search/tv?api_key=6a5be4999abf74eba1f9a8311294c267&query=Die%20Fosters&language=de&append_to_response=credits,external_ids,images&include_image_language=de,en,null</url>
2020-05-27 15:29:27.825 T:2875597680 DEBUG: CurlFile::Open(0xafbcf8f0) https://api.tmdb.org/3/search/tv?api_key=6a5be4999abf74eba1f9a8311294c267&query=Die%20Fosters&language=de&append_to_response=credits,external_ids,images&include_image_language=de,en,null
2020-05-27 15:29:28.027 T:2875597680 DEBUG: Get: Using "UTF-8" charset for "https://api.tmdb.org/3/search/tv?api_key=6a5be4999abf74eba1f9a8311294c267&query=Die%20Fosters&language=de&append_to_response=credits,external_ids,images&include_image_language=de,en,null"
2020-05-27 15:29:28.030 T:2875597680 DEBUG: scraper: GetSearchResults returned <results></results>
2020-05-27 15:29:28.030 T:2875597680 DEBUG: FindMovie: Searching for 'Die Fosters' using The Movie Database scraper (path: '/storage/.kodi/addons/metadata.tvshows.themoviedb.org', content: 'tvshows', version: '3.5.3')
2020-05-27 15:29:28.031 T:2875597680 DEBUG: scraper: CreateSearchUrl returned <url cache="tmdb-search-Die%20Fosters-de.json">https://api.tmdb.org/3/search/tv?api_key=6a5be4999abf74eba1f9a8311294c267&query=Die%20Fosters&language=de&append_to_response=credits,external_ids,images&include_image_language=de,en,null</url>
2020-05-27 15:29:28.034 T:2875597680 DEBUG: scraper: GetSearchResults returned <results></results>
2020-05-27 15:29:28.034 T:2875597680 WARNING: No information found for item '/media/Elements/Serien/Die Fosters/', it won't be added to the library.
die fosters — The Movie Database (TMDb) <= returns no results
the fosters — The Movie Database (TMDb) <= shows 3x series
So you might need to use the English series names for the scraper to match, even if the information the scraper subsequently downloads is the DE translation. Or you need to sign up with TMDB and add/edit the series to ensure the German alternative name is registered and returns results.
I didn't look into the other items, but it's likely the same root cause.